The allophanimidates used in this invention and their use as herbicides are disclosed and claimed in copending U.S. patent application Ser. No. 325,357, filed Jan. 22, 1973, by Julius J. Fuchs and Kang Lin, which is a continuation-in-part of copending U.S. patent application Ser. No. 181,201, filed Sept. 16, 1971, now abandoned. The use of these compounds in a method for altering plant flowering and sexual reproduction is the subject matter of copending U.S. patent application Ser. No. 328,059, filed Jan. 30, 1973, by Kang Lin, now U.S. Pat. No. 3,901,684. In addition, the use of these compounds in a method for increasing crop yields is disclosed and claimed in copending U.S. patent application Ser. No. 446,800, filed Feb. 28, 1974, by James D. Long, now U.S. Pat. No. 3,933,469 (which is a continuation-in-part of U.S. patent application Ser. No. 414,876, filed Oct. 12, 1973, which is, in turn, a continuation-in-part of U.S. patent application Ser. No. 348,323, filed Apr. 5, 1973, both now abandoned).
In particular, in U.S. Ser. No. 446,800, there is claimed a method for increasing the yield of wheat, rye, and corn crops comprising applying certain allophanimidates to the crop plant during inflorescence initiation or early development.
It has now been discovered that rice crop yields can be significantly increased by applying certain of these allophanimidates to rice seed, to rice seedlings, or to the soil into which these seeds or seedlings have been or will be placed.